This invention relates to a concrete mould side system comprising a side part that can be removably attached to a casting bed by means of one or more magnets.
Removable mould sides that are provided with different kinds of fastener solutions and designed for a concrete mould for casting elements from concrete have been disclosed in the prior art. These sides can be placed in desired positions on the casting bed depending on the size and shape of the object to be cast.
When wall elements are cast from concrete, the horizontal mould is usually a table mould, i.e. a tiltable mould with sides. A concrete dispenser moves above the table and allows a defined amount of mass to flow into the mould. Once the concrete is hardened, the table is tipped about a tilting axis provided on one side, into an almost upright position. The mould side that ends up in the upper position is removed, and the element is lifted away from the table using rings provided on its sides. The position of the upper side has to be adjustable according to the size of the element to be cast. Removable mould sides can be used for this purpose.
In addition, removable and adjustable mould side units enable door or window openings to be made at desired locations in the element.
The use of magnets for fastening removable mould sides is well known in the art. They are very suitable for fastening a mould side as they attach themselves to the flat steel surface of the casting bed. In order to secure a firm attachment of the mould side, strong magnets generating an attractive force of e.g. 15 kN must be used. In European patent application no. 99660050.8, a magnetic mould side fastening system is disclosed, wherein the frame of the magnet-carrying unit comprises a tilting axis about which the magnet unit can be tilted into a lower position, in which the magnet is contact with the casting bed, and into an upper position in which the magnet is not in contact with the casting bed. The mould side unit comprises a support on which the tilting axle of the magnet unit can be thus supported, that the unit is movable between a lower and an upper position, and the support has a gripping surface to which the upper surface of the magnet can be attached by means of attraction force when the magnet is tilted into its upper position about its tilting axle. The magnet is detached from the bed by means of a double acting lever.
This invention concerns a concrete mould side system comprising one or more mould side parts removably attached to a casting bed by means of one or more magnet units, wherein the magnet unit has a front face to be supported against the back face of the mould side part. The front face includes an oblique projecting member to be placed in an oblique counter-groove or hole provided in the back face of the mould side to press said front face and said back face together when the magnet unit is attached to the casting bed. The invention provides a system for fastening a magnet to a mould side, which system is simpler and more versatile than those previously known. A separate magnet unit comprises a tiltable permanent magnet. The magnet unit is fastened to a counterpart provided on the mould side by means of an oblique projecting member provided on its front face, engaging a corresponding groove in the counterpart. The front face of the magnet unit is designed to set at an angle of exactly 90xc2x0 to the casting bed when the magnet unit is fastened to the mould side, the front face of the magnet unit biting into the back face of the mould side due to the characteristic wedging groove action, and keeping the side upright all the time. In its fastened position, the magnet unit is always supported by the bottom surface of its rear end and by the side profile, since the bottom surface of the front end of the magnet is not in contact with the casting bed when the magnet is fastened to the mould side. Relative to the counter-groove in the mould side, the projecting member of the magnet unit can be directly complementary in shape, or it can be an oblique pin or tongue penetrating into an oblique hole, a saw-cut or the like forming the counter-groove.
The system according to the invention affects the mould side by the most direct vertical pressing force possible without using long levers. The internal forces of the system render the contact surface between the side and the magnet unit absolutely steady. The joint between the mould side and the casting bed is sealed at its front edge, and the mould side is prevented from falling backwards. The fastening is an easy and quick process, and the magnet can be coupled to any location on the mould side. This way of fastening makes it possible to place the mould side in the correct position without restrictions, and to release the fastening magnet without moving the mould side.
The system according to the invention may comprise a ready-to-use side profile having a running counter-groove for the magnet unit""s gripping member on its back face. The profile may be sold by the meter and can be cut into desired lengths. It can be made from steel, or for instance from extruded light alloy. The profile may form a mould side as such, or it may be provided with a front face of plywood, in one piece or divided into sections. Since the mould side comprises the guiding counter-groove, different kinds of openings, such as window and door openings, can easily be created therefrom by means of braces. Instead of having a continuous profile, the mould side can be provided with local, shorter oblique counter-grooves.
An important property of the magnet unit according to the invention is that it can be located at the joints between mould side units, where it not only attaches the side units to the bed but also joins them together. Using suitable fastening fittings, angle joints can also be formed.
In addition to the groove joint, the magnet unit can be fastened to the mould side unit with screws. Both the magnet unit""s front face and the upper surface perpendicular thereto are preferably provided with threaded holes. These fastening provisions make any local applications possible.
In the system according to the invention, readily available side and magnet parts can be used ex stock. The required equipment is thus easy to produce by combining standard parts. Moreover, the solution meets current requirements of ergonomics and automation (it is light and easy to clean, surfaces are even, robotics is applicable). The system also suits mould sides for products having openings, for all current product thicknesses manufactured in the concrete industry.